Question

我编写了一个由几个类组成的程序，但计算速度太慢（程序用粗体表示），我希望让我的java程序在GPU上运行以加速计算，或者是否有其他方法可以加速运行速度，如何更改我的代码？程序的计算如下：

public class ComputeThreadPool {
  public static double[][] distance = new double[40][8];
  public static HashMap<String,Double> simMap = new HashMap<String,Double>();
static class WorkThread implements Runnable {
    private Map<String, Double> testWordTFMap;
    private Map<String, Double> trainWordTFMap;
    private Map<String, double[]> words;
    private String trainname;

    public WorkThread(Map<String, Double> map1, Map<String, Double> map2, Map<String, double[]> words,String trainname) {
        this.testWordTFMap = map1;
        this.trainWordTFMap = map2;
        this.words = words;
        this.trainname=trainname;
    }

    @Override
    public void run() {
         System.out.println(Thread.currentThread().getName()+" Start. Command = "+command);
        double mul = 0, testAbs = 0, trainAbs = 0;

        WordsSimilarity computeS = new WordsSimilarity();
        double wf = 0;
        Set<Map.Entry<String, Double>> testWordTFMapSet = testWordTFMap.entrySet();
        for (Iterator<Map.Entry<String, Double>> it = testWordTFMapSet.iterator(); it.hasNext(); ) {
            Map.Entry<String, Double> me = it.next();
            Set<Map.Entry<String, Double>> trainWordTFMapSet = trainWordTFMap.entrySet();
            ***for (Iterator<Map.Entry<String, Double>> it2 = trainWordTFMapSet.iterator(); it2.hasNext(); ) {
                Map.Entry<String, Double> me2 = it2.next();              
                    wf = computeS.similarity(me.getKey(), me2.getKey(), words);
                if (wf > 0.45)
                    mul += wf * me.getValue() * me2.getValue();
            }
        }***

        for (Iterator<Map.Entry<String, Double>> it3 = testWordTFMapSet.iterator(); it3.hasNext(); ) {
            Map.Entry<String, Double> me3 = it3.next();
            testAbs += me3.getValue() * me3.getValue();
        }
        testAbs = Math.sqrt(testAbs);
        Set<Map.Entry<String, Double>> trainWordTFMapSet = trainWordTFMap.entrySet();
        for (Iterator<Map.Entry<String, Double>> it4 = trainWordTFMapSet.iterator(); it4.hasNext(); ) {
            Map.Entry<String, Double> me4 = it4.next();
            trainAbs += me4.getValue() * me4.getValue();
        }

        trainAbs = Math.sqrt(trainAbs);
        simMap.put(trainname,mul / (testAbs * trainAbs));
        System.out.println(Thread.currentThread().getName() + " Start.     " );
        processCommand();
        System.out.println(Thread.currentThread().getName() + " End.");
    }
    private void processCommand() {
        try {
            Thread.sleep(5);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}

public static HashMap<String,Double> main(Map<String, Double> testWordTFMap,Map<String, TreeMap<String, Double>> trainFileNameWordTFMap,Map<String, double[]> words) {
    int num=0;
    ExecutorService executor = Executors.newFixedThreadPool(6);
    Set<Map.Entry<String,TreeMap<String,Double>>> trainFileNameWordTFMapSet = trainFileNameWordTFMap.entrySet();
    for(Iterator<Map.Entry<String,TreeMap<String,Double>>> it = trainFileNameWordTFMapSet.iterator(); it.hasNext();){
        Map.Entry<String, TreeMap<String,Double>> me = it.next();
        num=num++;
        Runnable worker = new WorkThread(testWordTFMap,me.getValue(),words,me.getKey());
        executor.execute(worker);
    }
    executor.shutdown();
    while (!executor.isTerminated()) {
    }
    System.out.println("Finished all threads");

    return simMap;
}

}

wf的计算方法如下：

    public static double similarity(String word1, String word2,Map<String, double[]> words) {

    double[] count1=words.get(word1);
    double[] count2=words.get(word2);
    double sum=0;
    double Abs1=0;
    double Abs2=0;
    if(count1 == null || count2 == null) {
        return 0;
    }
    for (int c = 0; c < count1.length; c++) {
        sum += count1[c] * count2[c];
        Abs1 += count1[c] * count1[c];
        Abs2 += count2[c] * count2[c];
    }
    return sum / (Abs1 * Abs2);

}

Answer 1

您需要找到在GPU上运行的JVM实现或者运行标准JVM的GPU的运行时环境/ shell;但除非JVM是为GPU构建的，否则您可能会或可能不会获得性能提升。

但是我会说，你应该能够首先在代码中找到优化。比如使用增强的for循环。除了计算单词的相似性之外，似乎并没有那么多应该导致运行时间过长。

如何让我的java程序在GPU上运行？如何更改我的程序可以加速？

1 个答案: